feat: robust metric extraction with confidence score and proof snippets

- fixed Year-Prefix Bug in MetricParser
- added metric_confidence and metric_proof_text to database
- added Entity-Check and Annual-Priority to LLM prompt
- improved UI: added confidence traffic light and mouse-over proof tooltip
- restored missing API endpoints (create, bulk, wiki-override)

company-explorer/frontend/node_modules/update-browserslist-db/index.d.ts

@@ -0,0 +1,6 @@
+/**
+ * Run update and print output to terminal.
+ */
+declare function updateDb(print?: (str: string) => void): void
+
+export = updateDb